Divertor heat flux mitigation by supersonic molecular beam injection in HL-2A ELMy H-mode plasmas

Abstract

Abstract:

Using infrared (IR) thermography, power loads onto the divertor plates are investigated in ELMy H-mode plasmas on HL-2A. Divertor heat flux mitigation has been achieved by using supersonic molecular beam injection (SMBI), characterized by a large reduction in peak heat flux and a sharp increase of edge localized mode (ELM) frequency. After SMBI fuelling, the large-scale filaments generated by ELMs are suppressed and sheared off to small-scale ones. Moreover, the plasma radiation losses in the scrape-off layer (SOL) and divertor are increased after the SMBI. All of them contribute to the significant reduction of full energy deposition onto the divertor targets after the SMBI.

Key words: Edge localized mode, Supersonic molecular beam injection, Heat flux mitigation, Infrared thermography

摘要：

在HL-2A 装置上优化和发展了偏滤器靶板上的红外测温系统，并利用该系统分析了高约束模放电期间边缘局域模的热沉积分布特性。在高约束模式放电期间，超声分子束注入使边缘局域模所引起的偏滤器靶板上瞬间热通量峰值下降了~60%，并伴随着边缘局域模爆发频率增加了2~3 倍，而等离子体储能仅下降了~8%。分析结果表明，大幅度的丝状结构在超声分子束注入之后得到了有效抑制，沉积到偏滤器靶板上的瞬间热通量峰值也随之下降。此外，在超声分子束注入之后偏滤器室内的热辐射损失大幅度增加，从而耗散了热输运所携带的部分能量，进一步分散了沉积到偏滤器靶板上的能量，有效地保护了偏滤器靶板。

关键词: 边缘局域模, 超声分子束注入, 热通量缓解, 红外测温系统

CLC Number:

TL61+2

GAO Jin-ming, CHENG Jun, YAN Long-wen, LI Wei, NIE Lin, FENG Bei-bin, CHEN Cheng-yuan, Lu Jie, YI Ping, JI Xiao-quan, ZHOU Yan, LIU Yi, YANG Qing-wei. Divertor heat flux mitigation by supersonic molecular beam injection in HL-2A ELMy H-mode plasmas[J]. NUCLEAR FUSION AND PLASMA PHYSICS, 2015, 35(1): 1-7.

高金明，程钧，严龙文，李伟，聂林，冯北滨，陈程远，卢杰，易萍，季小全，周艳，刘仪，杨青巍. HL-2A 装置超声分子束注入缓解偏滤器靶板上边缘局域模热通量研究[J]. 核聚变与等离子体物理, 2015, 35(1): 1-7.

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